Knitted garments are manufactured in separate portions, such as the body of a sweater or shirt, the collar, sleeve, cuff, etc. Complete garments are thereafter stitched together from various portions. A continuously operating knitting machine is programmed to produce a continuous web comprised of succeeding identical garment portions, e.g. a continuous web of knitted shirt collars, with succeeding garment portions being joined by a knitted-in separating thread.
Each garment portion has a finished and an unfinished edge. The finished edge is the one exposed to view when the garment portion is assembled in the completed garment, e.g. the edge of a cuff. The unfinished edge is sewn into the seam joining the garment portion to the remainder of the garment.
A knitting machine may use one or more spools or supplies of yarn or thread. A predetermined number of rows of a particular color or type of yarn or thread is knitted. Then the knitting machine may switch to another type of yarn or thread and continue the knitting process. Upon completion of a single garment portion in a continuous web of garment portions, the knitting machine is programmed to finish the edge of the garment portion in the web to make the finished edge so that it will not unravel. Then, without interrupting the continuous knitting process, the machine switches to what is known in the art as a spearating thread, and one or more rows of separating thread is knitted. Thereafter, the machine switches back to the original yarn and begins knitting the next garment portion in the web starting at the edge of that portion which is raw and unfinished. Each succeeding garment portion in the web is thus joined to the respective preceding garment portion by separating thread. The continuous web is wound on a beam and the beam is brought to where garments are to be made.
Before garments are manufactured from the garment portions produced in the continuous web, the separating thread between adjacent garment portions must be removed. It is conventional to manually remove the separating thread by pulling it out and/or unraveling the separating thread, or to perform this removal and/or unraveling procedure semi-automatically, with an operator holding the garment while the separating thread is pulled out.
Because of time delays associated with the manual or semi-automatic steps in removing separating thread, it is also known to form the separating thread out of a material that is soluble in water or other appropriate fluid. The web of garment portions is passed through heated, even boiling, water or other appropriate solvent and the correspondingly selected separating thread is melted and dissolves away leaving the separate, but not wet and perhaps somewhat damaged, garment portions. An appropriate drying procedure is thereafter needed, requiring expenditure of extra time and effort.
Finally, it is known to form the separating thread of a material that deteriorates in the presence of heat. Attempts have been made to develop a dry process using such a separating thread formed from a specially developed synthetic filament. With the application of hot air or radiant heat, the thread would melt or materially deteriorate so as to separate the knitted garment portions. This has led to the significant problem of the presence of a separating thread residue on the finished (upstream) edge of all of the separated garment portions. In addition to eliminating the residue on the finished edge of the garment portion, it is advantageous to use a synthetic material for the separating thread whose melt temperature is lower than that of the yarn used to form the garment portion. This would, of course, be a problem in connection with garment portions of synthetic filament yarns.